Call for comments - RFC 36

[Daniel Morissette]

Steve Lime wrote:
> Hi all: I (with the help of Tom K.) put together an RFC outlining better template support
> for queries via the CGI interface.  Please take a look at:
> 
>   http://mapserver.gis.umn.edu/development/rfc/ms-rfc-36/ 
> 

Steve, Tom,

I like it. I have a little fear at the back of my mind that there might 
be some aspects/issues that we didn't think of and are not covered, but 
overall that sounds great.

Here are a few comments and answers to some questions that you raised in 
the document:

1- Do we need to require that start/end tags be on their own line?

This is handled by getInlineTag(). I didn't test, but from a quick 
browse of the code I think they can be anywhere on a line. That would 
remain to be verified of course. Some of the template parsing functions 
added for the HTML template stuff may not be optimal and could possibly 
use some optimization work.

2- Dig Dan's proposal for a queryable flag out of the -dev archives.

Here is what I had written when we discussed the terminology cleanup RFC:

> An option might be to add a QUERYABLE TRUE/FALSE keyword to the layer and class objects, that would determine whether a layer/class is queryable or not. Then to query through the CGI you'd also need to provide a template (or otherwise mapserv would issue an error saying that TEMPLATE was not provided). The big benefit is that MapScript apps (and WMS services) would no longer need to provide dummy templates. 

3- Backwards incompatibilities:

You wrote "No other compatibility issues are anticipated." which implies 
that the reader needs to dig through the text of hte RFC to find out hte 
list of incompatibilities. I think they should be explicitly listed in 
that section again. Off the top of my head they would be:

- TEMPLATE keyword removed from LAYER/CLASS and moved to OUTPUTFORMAT
- QUERYABLE parameter must be used to mark layers as queryable
- Template format has changed. Now [resultset] and [feature] blocks in 
the main template replace former header/footer templates
- ... Did I miss any?

4- With this new system do we lose the benefit of being able to reuse 
templates, headers and footers between layers? Now we'd need to 
duplicate them for each layer inside the [resultset] blocks, could that 
become an issue for very large mapfiles?

5- Do we want to allow listing multiple layers in the [resultset 
name=...] arg so that a multiple layers can share the same [resultset] 
block?

6- How'bout allowing [resultset group=...] as well?


Daniel
-- 
Daniel Morissette
http://www.mapgears.com/